But I Don’t Eat that Much!

I wrote Food Truths, Food Lies after spending years trying to help my patients sort through their food and weight issues. There is plenty of research showing how bad we all are at estimating how many calories we eat. We can be off by hundreds of calories when quizzed about portion size! This universal ‘bad guessing’ is one of the biggest reasons Americans are so big.

As food portions have grown over the years, our ability to accurately judge calorie content hasn’t. I recently came across another study that looks at this issue from a little different angle.

This 2006 study is by my favorite ‘Food Psychologist’ Brian Wansink. He and his co-author used different size meals to figure out if the “who” or “what size” was more important in judging calorie counts.

It would be easy (and wrong, according to Dr. Wansink) to imagine that overweight or obese people are worse at judging how many calories are in their food. This understanding had been used to explain obesity in the past.

What Dr. Wansink found was that it is actually the size of the meal, not who was going to eat it that caused the mistake in guessing calories. Normal weight and obese people could both get it nearly right when the portion size was small. The surprising part of his results was that both normal weight people and obese people got further and further away from being accurate as the portion size got larger.

I think this makes it clear that portion ‘up-sizing’ is very much part of the problem. Choosing larger portions misleads the eater into thinking they are eating less than they really are. If I say, “But I don’t eat that much!” to defend my weight or eating habits, I’ll always be wrong.

‘Value-sized’ portions may be one of the most important reasons why. The ‘value’ we imagine we’re getting from these larger sizes is not about saving money. No one can eat enough at one meal to not be hungry the next day.

I fear that the only ‘value’ to be had in these jumbo portions is about our ‘value’ to some big company. How many more diet programs we’ll buy, how many more diabetes pills we’ll need, how much sooner we’ll need open heart surgery. Not the kind of ‘value’ I want to be shopping for!